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Twenty-one mixed-parity (average 2.4 ± 0.49) crossbred sows and their offspring were used to determine whether sow milk leptin at farrowing was related to neonatal serum leptin and pig growth to weaning. During farrowing, pigs were randomly allotted to suckling (n = 99) or delayed suckling (n = 89) groups, with delayed suckling pigs placed in a group pen apart from the dam before suckling. Both groups had access to heat lamps. Colostrum samples were collected no more than 2 h after farrowing the first pig. Blood samples were collected from all pigs approximately 2 h after farrowing was complete; pigs were then ear notched and returned to their dams. Pig BW was recorded at 1.2 ± 0.04 d of age and again at weaning. Milk and blood serum were collected after centrifugation; leptin concentrations were estimated using RIA. Leptin was detected in colostral milk, as expected, and averaged 46.0 ± 1.1 ng/mL. Pig serum leptin (P< 0.02) was greater in suckling pigs than in delayed suckling pigs, averaging 0.69 ± 0.08 and 0.54 ± 0.07 ng/mL, respectively. Although male pigs were heavier (P< 0.01) at birth than female pigs (1,507 ± 52 vs. 1,381 ± 43 g), ADG to weaning and weaning weights were similar for both sexes, averaging 229 ± 14 g and 5,829 ± 323 g, respectively, for all pigs; serum leptin concentrations were not affected by sex of the pig. Milk serum leptin was not associated with litter size, parity, pig birth weight, ADG to weaning, or weaning weight. Suckling status did not influence ADG to weaning or weaning weight of pigs; neonatal pig serum leptin was not related to birth weight, weaning weight, or ADG to weaning. These results indicate that leptin is not directly related to early neonatal growth in the pig; however, more in-depth studies are needed to determine possible indirect or long-term effects of early leptin exposure.

The productivity of ethanol fermentation processes, predominantly based on batch operation in the U.S. fuel ethanol industry, could be improved by adoption of continuous processing technology. In this study, a conventional yeast fermentation was coupled to a flat-plate membrane pervaporation unit to recover continuously an enriched ethanol stream from the fermentation broth. The process employed a concentrated dextrose feed stream controlled by the flow rate of permeate from the pervaporation unit via liquid-level control in the fermentor. The pervaporation module contained 0.1m² commercially available polydimethylsiloxane membrane and consistently produced a permeate of 20%-23% (w/w) ethanol while maintaining a level of 4%-6% ethanol in a stirred-tank fermentor. The system exhibited excellent operational stability. During continuous operation with cell densities of 15-23g/l, ethanol productivities of 4.9-7.8g l^-1 h^-1 were achieved utilizing feed streams of 269-619g/l glucose. Pervaporation flux and ethanol selectivities were 0.31-0.79l m^-2 h^-1 and 1.8-6.5 respectively.

Haematology and blood biochemistry were monitored during the development and regression of psoroptic scabies in sheep. There were rises in numbers of neutrophils and eosinophils and in the fibrinogen concentrations, with lowered haemoglobin concentrations any lymphocyte numbers. The only biochemical parameters that were affected were the estimated serum globulin concentration, which rose during the disease process, and the serum albumin concentration, which fell. All of these changes reverted to normal soon after treatment.

Examination of possible transmission of the Irish strain of the sheep scab mite (Psoroptes ovis) of ovine origin between host species involved calves and goats being placed with infected sheep and also directly challenged with live mites. Although mites remained on recipient species for up to a week, they failed to produce disease in either of these species. Calves and goats that had live mites placed on them likewise failed to infect sheep with which they were housed.

Psoroptes ovis mites were removed from infected sheep and placed in positions where wool and mites normally accumulate during sheep scab outbreaks. The ambient temperature and humidity were monitored over a 3-week period and the survival and infectivity times were examined. The procedure was carried out during each of the seasons. The hatchability of mite eggs was also examined. It was found that little variation occurred between seasons, with mites regularly retaining viability and infectivity for 15 days during all seasons. Mites that survived for more than 16 days failed to infect sheep. Mite eggs retained hatchability for up to 7 days.

CTP synthetase (EC 6.3.4.2, UTP:ammonia ligase (ADP-forming)) activity in Saccharomyces cerevisiae is allosterically regulated by CTP product inhibition. Amino acid residue Glu161 in the URA7-encoded and URA8-encoded CTP synthetases was identified as being involved in the regulation of these enzymes by CTP product inhibition. The specific activities of the URA7-encoded and URA8-encoded enzymes with a Glu161 --> Lys (E161K) mutation were 2-fold greater when compared with the wild-type enzymes. The E161K mutant URA7-encoded and URA8-encoded CTP synthetases were less sensitive to CTP product inhibition with inhibitor constants for CTP of 8.4- and 5-fold greater, respectively, than those of their wild-type counterparts. Cells expressing the E161K mutant enzymes on a multicopy plasmid exhibited an increase in resistance to the pyrimidine poison and cancer therapeutic drug cyclopentenylcytosine and accumulated elevated (6-15-fold) levels of CTP when compared with cells expressing the wild-type enzymes. Cells expressing the E161K mutation in the URA7-encoded CTP synthetase exhibited an increase (1.5-fold) in the utilization of the Kennedy pathway for phosphatidylcholine synthesis when compared with control cells. Cells bearing the mutation also exhibited an increase in the synthesis of phosphatidylcholine (1.5-fold), phosphatidylethanolamine (1.3-fold), and phosphatidate (2-fold) and a decrease in the synthesis of phosphatidylserine (1.7-fold). These alterations were accompanied by an inositol excretion phenotype due to the misregulation of the INO1 gene. Moreover, cells bearing the E161K mutation exhibited an increase (1.6-fold) in the ratio of total neutral lipids to phospholipids, an increase in triacylglycerol (1.4-fold), free fatty acids (1.7-fold), and ergosterol ester (1.8-fold), and a decrease in diacylglycerol (1. 3-fold) when compared with control cells. These data indicated that the regulation of CTP synthetase activity by CTP plays an important role in the regulation of phospholipid synthesis.

The design of the fingertip sensing subsystem constructed for use in a dextrous underwater gripper is presented. Two distinct types of sensor were developed specifically for this application, a force sensor and a slip sensor. The force sensor is used to determine the force exerted by the gripper on the target object, and hence to allow the force hop closure required to carry out dextrous manipulation and to handle delicate marine samples. The function of the slip sensor is to detect the occurrence of slippage between the fingertip and the target, and this information can be used in a variety of ways: for example, providing a warning system to the force control loop or enhancing the gripper's exploratory capabilites in areas of poor visibility. Due to changes in ambient pressure, the force sensor is a simple robust device based on strain gauge technology developed specifically for this application. The sensor is capable of being incorporated on an artificial fingertip mounted at the extremity of the finger of a dextrous gripper. The slip sensor is an extremely small P VDF-based device capable of being shaped to suit the curvature of the fingertip. An analysis of both sensors' operation is presented, along with calibration measurements and results for the first prototypes.